CXCL12 and colorectal cancer: CXCL12-CXCR4 axis [227], and microRNAs, e.g., miR-302e in colorectal cancer [208], miR-145-5p in colorectal cancer [228], and miR-1-3p in rectal adenocarcinoma [229], whose expression is decreased in colorectal cancer tumors.